This invention relates generally to an absorption chiller and, in particular, to preventing the chilled water evaporator tubes from rupturing in the event the chilled water flow through the evaporator is inadvertently terminated while the system is operating.
When the chilled water flow through an absorption chiller is closed down for some reason, the chiller""s controls will sense the condition and take steps to shut the machine down. However, during the time that the flow stoppage is detected and the shut down procedures carried out, there is no heat input to the evaporator heat exchanger that is normally provided by the chilled water flow. As a consequence, because of the machines thermal inertia, the evaporators saturation temperature can drop substantially to a point below the freezing temperature of the water in the evaporator tubes causing the water in the tubes to freeze. This, in turn, can lead to the evaporator tubes rupturing resulting in the need for an extended machine down time while expensive repairs are carried out.
It is therefore an object of the present invention to improve absorption chillers.
A further object of the present invention is to protect the chilled water tubes inside of the evaporator of an absorption chiller from rupturing in the event the chilled water flow through the chiller is closed down for some reason while the chiller is operating.
A still further object of the present invention is to provide heat to the evaporator of an absorption chiller in the event the chilled water flow to the evaporator is inadvertently closed down.